1. Field of the Invention
This invention relates to a method of winding a magnetic recording tape such as a video recording tape or an audio recording tape wound on one winding frame, onto another winding frame such as the hub or the reel of a cassette or a cartridge, and more particularly to a method of winding such a recording tape fed from a tape source in the form of a large winding frame on which a long roll tape is wound, onto a small winding frame when manufacturing a tape cassette, a tape cartridge or the like.
2. Description of the Prior Art
There is known a tape winding apparatus for dispensing a long roll magnetic recording tape wound on a large tape source reel in predetermined lengths onto smaller reels or hubs. In the known tape winding apparatus, the tape speed at which the magnetic recording tape is wound on the smaller reel is carefully controlled so that the tape is wound on the smaller reel in a desirable state in a short time without the tape being stretched and without the winding surface being brightened. Typically the tape speed is gradually increased to a high speed at the beginning stage of each winding cycle, is then kept at the constant high speed and is gradually slowed down at the end of the winding cycle to be finally stopped, or the tape speed is gradually increased to a high speed at the beginning stage of each winding cycle, is then kept constant at the high speed, is gradually slowed down to a lower speed near the end of the winding, is kept constant at the lower speed for a while, and then is completely stopped. Further in the known winding apparatus, a tension arm is provided to give proper tension to the running tape with a predetermined tension pattern. For example, a relatively strong tension is imparted to the tape at the beginning stage of each winding cycle and a relatively weak tension is imparted to the tape near the end of each winding cycle. Particularly, when the tape is extremely thin, uneveness of winding is apt to be generated unless tension is imparted to the tape with said predetermined tension pattern. Known systems for controlling the tape speed include a feed-back control system and a capstan-pinch-roller system.
However the capstan-pinch-roller system is not suitable for high speed winding since it cannot follow rapid changes in tape tension. Although the feedback control system is suitable for high speed winding, the conventional feed-back control system has the drawback that the electric circuit thereof is complicated and accordingly the system is expensive. For example, in the tape winding apparatus employing the feed-back control system disclosed in Japanese Patent Publication 56(1981)-26904, the feed-back control system comprises a reference voltage generator and a comparator; a voltage corresponding to the measured tape running speed is compared, by the comparator, with the reference voltage outputted from the generator to control the tape running speed. Therefore, the electric circuit of the feed-back control system is inherently complicated and expensive.